Plastic containers



Dec. 1, 1964 I A. FISCHBACH 3,159,305

PLASTIC CONTAINERS Filed Feb. 28, 1963 United States Patent 3,159,365 PLASTIC CONTAMRS Alfred Fischhach, Runderoth, Rhineland, Germany Filed Feb. 28, 1963, Ser. No. 261,763 Claims priority, application Germany Sept. 22, 1962 3 Claims. (Cl. 220-60) This invention relates to containers, and more particularly to containers of plastic material such as oil cans;

Containers of such general type are filled automatically at filling stations, and are closed or sealed automatically following the filling operation. To achieve as great a line production of oil containers as is possible, the closing or sealing means must be so constructed that the closing or sealing operation can be effected securely and quite rapidly. Of even greater importance is the fact that the closing or sealing operation of the containers must not exceed the time element required for the filling cycle, since it is only under such circumstances that a satisfactory function of the filling station at a uniform operating rhythm is assured.

To meet such requirement, it has been proposed to employ an oil container or can having an opening flange or funnel adjoining the filling opening, with the funnel surfaces being welded or secured together subsequent to the filling cycle. While containers have also been used which, after the filling cycle, are provided with a lid or cover, with the upper rim of the container and the rim of the lid or cover being folded together tightly. Of course, such closing procedures require expensive closing tools or appliances.

In order to avoid this disadvantage, it has been proposed to provide a closure which can be applied very quickly, and without the necessity of special equipment. Such quick closures include essentially a sealing cup which is inserted into the filling opening, and retained in the closed position by means of a locking ring coacting with the cup such as by overlapping. To avoid the necessity of a special locking ring, it has been proposed to provide the cup with an annular rim directed radially outward, which rim is adapted to engage in sealing fashion an annular groove formed in the rim or flange of the filler opening. This particular construction presents the problem that with a sudden rise in the inner pressure within the container, the closure may be loosened or otherwise disadvantageously effected as regards its sealing position. Such can arise, for example, if the container is thrown or is crushed in storage.

An important object of the present invention is to provide a closure for containers of the type under consideration, which will overcome the above and other disadvantageous features present in the art.

A further object of the invention is to provide a closure which will remain tight under all conditions, and which closure when inserted in the filler opening can no longer be opened from the outside.

An additional object of the invention is to provide a container of synthetic material, particularly an oil can in which the filler opening is closed following the filling operation by means of a cup-shaped permanent closure which is pressed in the filler opening.

To accomplish the above and other objects, the invention comprises a closure member or lid having a domed bottom wall, a side wall extending upwardly from the bottom wall with the inherent elasticity of the closure member urging such side wall to lie tightly against the surface of a beadlike formation provided for the top of the container body and with the upper margin of the closure member which includes an enlarged conical surface fitting in a sealing manner in a groove of the filler opening component located directly above the bead-like formation ice with such component further embodying a flange means overlapping such upper margin for holding the closure member or lid securely in the closed position.

Further objects and advantages of the invention will become more fully apparent from the following detailed description and annexed drawings, and in which drawmgs:

FIG. 1 is a vertical sectional view of the closure member or lid;

FIG. 2 is a vertical fragmentary sectional view showing the closure member inserted into the filler opening; and

FIG. 3 is a side elevational view of the container.

As shown in the drawings, a container 5 such as an oil can of synthetic material is formed with a filler opening denoted generally 0 in its top wall 6, and such opening is adapted to be closed by a permanent closure member or lid 1. In order to permit the contents of the container to be discharged or dispensed, the top wall 6 is provided with protuberances 13 which may be cut open or cut 01f as illustrated by the dash-dot lines in FIG. 3.

To form the filler opening, the top wall 6 is shaped to provide a bead-like formation 9 which extends toward the axis of the container and the major portion of such formation lies below the top Wall 6. Integrally formed with the bead-like formation is a vertical wall portion 7 which terminates in an inwardly extending horizontal flange By virtue of the bead-like formation shown, it will be appreciated that the flange 8 is located quite close to the top wall 6 which means that the components constituting the filler opening are of relatively short height dimensions, thereby enabling the containers to be easily and readily stacked.

The closure member or lid 1 is generally cup-shaped and includes a domed bottom wall 2, a side wall 3 and an upper margin 4. A vertical portion 11 is provided at the outer edge of the wall 2, and such portion merges with wall portion 12 which is inclined inwardly and downwardly from the side wall 3. Also, the margin 4 extends outwardly of the side wall 3, and is provided with a conical surface 4a.

When the closure or lid 1 is pressed into the filler opening 0, the side wall 3 sealingly engages the bead-like formation (FIGURE 2) by reason of inherent elastic deformation. The magin 4 also engages the groove 10 in a similar fashion, and the portion 11 imparts to the closure 1 a reinforcement at its lower portion so that the side Wall 3 which is compressed by the bead like formation 9 is drawn downwardly around the surface of the bead-like formation so that the margin 4 will spring upwardly due to its conical surface 4a and rest firmly against the flange 8. At the same time, the flange 8 secures the closure or lid 1 in its sealing position.

With rising pressure within the container 5, the wall portion 12 functions as a component of pressure defined by the components resulting from the vertical pressure force and from the lateral deflection force of the bottom of the closure or lid whereby develops at such area a support surface of high rigidity.

From the foregoing, it will be seen that the closure or lid thus located in the filler opening cannot be removed from the outside of the container, or least without destruction or visible deformation of the opening components and the lid. The protuberances 13 are used as the means for permitting the container contents to be discharged.

The invention is not to be confined to any strict conformity to the showings in the drawings, but changes or modifications may be made herein so long as such changes or modifications mark no material departure from the spirit and scope of the appended claims.

l. A container of synthetic material, particularly a container for oil, including a body portion having a top wall, means defining a filler opening in said top wall of lesser p'eri'metric dimension than that of ithe body portion and a closure fmem'be'r for said filler opening, said closure member comprising a 'domedbottom wall, a vertical side wall extending upwardly therefrom and an enlarged upper margin having a conical surface, said filler opening defining means including a bead-like formation on the top Wall extending into the interior of the body portion, a vertical wall adjoining said bead-like portion and projecting upwardly therefrom, and an inwardly directed horizontal flange at the free end of the vertical wall whereby due to the inherent elasticity of the closure member, when the closure member is inserted into the filler opening, the vertical side wall of such member lies tightly 'against said bead-like formation and said enlarged upper margin fits tightly in the groove defined adjacent the juncture between the bead-like formation and said vertical wall and said flange overlaps said upper margin thus holding the closure member in its sealing position.

.2. :A container of" synthetic material, particularly a container for oil,.including a body portion having a top wall, means defining a filler opening in the top wall and a closure member for the filler opening, said closure member comprising adorned bottom wall, a vertical side wall, a surface between the vertical side wall and the domed bottom wall inclined downwardly toward the central axis of the body portion, and an enlarged upper margin having a conical surface, said filler opening defining means including a bead-like formation for the top wall extending into the body portion, a vertical Wall adjoining the bead-like formation, and an inwardly directed horizontal flange at the free end of the vertical wall whereby due to the inherent elasticity of the closure member, when the closure member is inserted into the filler opening, the vertical side wall of the closure member lies tightly against the bead-like formation and the enlarged upper margin fits tightly in the groove defined adjacent the juncture between the bead-like formation and v d the vertical wall and the flange overlaps the enlarged upper margin thus holding the closure member in its sealing position and with rising pressure within the body portion, the downwardly inclined surface provides a support of high rigidity.

3. A container of synthetic material, particularly a container for oil, including a body portion having a top wall, means defining a filler opening in the top wall and a closure member for the filler opening, said closure member comprising a domed bottom wall, a vertical side wall, a surface between the vertical side Wall and the domed bottom inclined downwardly toward the central axis of the bodyportion, and'an enlarged upper margin having a conical surface, said filler opening defining means including a bead-like formation for the top 'wall extending into the body portion, a vertical wall adjoining the bead-like portion, an inwardlydirected horizontal flange at the free end of the vertical wall, and the major portion of said bead-like formation being located below the top wall whereby the horizontal flange 'is positioned in close proximity to the top wall, the arrangement being such that due to the inherent elasticity of the closure member, when the closure member is inserted into the filler opening, the vertical side Wall of'the closure member lies tightly against the bead-like formation and the enlarged upper margin fits tightly in the groove defined adjacent the juncture between the bead-like formation and the vertical wall and the horizontal flange overlaps the enlarged upper margin thus holding the closure member in its sealing position and with rising pressure within the body portion, the downwardly inclined surface provides a support of high rigidity.

References Cited inthefile of this patent UNITED STATES PATENTS 

1. A CONTAINER OF SYNTHETIC MATERIAL, PARTICULARLY A CONTAINER FOR OIL, INCLUDING A BODY PORTION HAVING A TOP WALL, MEANS DEFINING A FILLER OPENING IN SAID TOP WALL OF LESSER PERIMETRIC DIMENSION THAN THAT OF THE BODY PORTION AND A CLOSURE MEMBER FOR SAID FILLER OPENING SAID CLOSURE MEMBER COMPRISING A DOMED BOTTOM WALL, A VERTICAL SIDE WALL EXTENDING UPWARDLY THEREFROM AND AN ENLARGED UPPER MARGIN HAVING A CONICAL SURFACE, SAID FILLER OPENING DEFINING MEANS INCLUDING A BEAD-LIKE FORMATION ON THE TOP WALL EXTENDING INTO THE INTERIOR OF THE BODY PORTION, A VERTICAL WALL ADJOINING SAID BEAD-LIKE PORTION AND PROJECTING UPWARDLY THEREFROM, AND AN INWARDLY DIRECTED HORIZONTAL FLANGE AT THE FREE END OF THE VERTICAL WALL WHEREBY DUE TO THE INHERENT ELASTICITY OF THE CLOSURE MEMBER, WHEN THE CLOSURE MEMBER IS INSERTED INTO THE FILLER OPENING, THE VERTICAL SIDE WALL OF SUCH MEMBER LIES TIGHTLY AGAINST SAID BEAD-LIKE FORMATION AND SAID ENLARGED UPPER MARGIN FITS TIGHTLY IN THE GROOVE DEFINED ADJACENT THE JUNCTURE BETWEEN THE BEAD-LIKE FORMATION AND SAID VERTICAL WALL AND SAID FLANGED OVERLAPS SAID UPPER MARGIN THUS HOLDING THE CLOSURE MEMBER IN ITS SEALING POSITION. 